Van ryan



Jan. 24, 1956 VAN Y N 2,732,456

LOCK-IN CIRCUIT INTERRUPTER Filed May 19, 1951 4 Sheets-Sheet l M INVENTOR, j t crariy Jan. 24, 1956 A. VAN RYAN 2,732,456

LOCK-IN CIRCUIT INTERRUPTER Filed May 19, 1951 4 Sheets-Sheet 2 llllll INVENTOR. j fldlrmy V4211 @4212 7 55 BY Jan. 24, 1956 A. VAN RYAN LOCK-IN CIRCUIT INTERRUPTER 4 Sheets-Sheet 3 Filed May 19, 1951 INVENTOR.

United States Patent LOCK-IN CIRCUIT INTERRUPTER Anthony Van Ryan, South Milwaukee, Wis., assignor to McGraw Electric Company, Milwaukee, Wis., a corporatiou of Delaware Application May 19, 1951, Serial No. 227,149

4 Claims. (Cl. 20089) This invention relates to a lock-in reclosing circuit in terrupter.

Objects of this invention are to provide a circuit interrupter which may have one or more quick interrupting operations followed by one or more slow operations or, in other words, which is so made that it has two timecurrent characteristics.

Further objects are to provide a circuit interrupter which looks itself in closed position after one or more circuit interrupting operations so that if a fault remains after the last reclosing for which the device is set, a fuse in circuit with the interrupter will blow and thus isolate that section of the system on which the fault remains.

Further objects are to provide a circuit interrupter which may have each of the two characteristics hereinabove enumerated, that is to say, which may have two time-current characteristics, the slow one being so arranged to allow the normal blowing of a fuse which would customarily be placed after the circuit interrupter, unless the fault were cleared during the preceding interruptions, and which is arranged to lock itself closed after a predetermined number of operations so that whether the fuse is coordinated with the circuit interrupter or not, the fuse following the circuit interrupter will blow on continued overload when the circuit interrupter locks itself closed.

Further objects are to provide a circuit interrupter which has a single cumulative means for both locking the circuit interrupter closed and for producing the two time-current characteristics.

Further objects are to provide a circuit interrupter which may have the characteristics hereinabove enumerated or which may be so adjusted that all of the operations may be rapid or may be retarded depending on the adjustment of the apparatus.

Further objects are to so construct the above described cumulative means that it has the ability to reset itself after any number of operations up to and including its maximum number so that the circuit interrupter Will be ready for repeated cycling as described hereinabove after the cumulative means has automatically reset itself.

Further objects are to provide a dual function cumulative means having the characteristics hereinabove enumerated which is hydraulically operated and does not depend upon delicate escapement mechanism or other mechanism of this general type but which may be made in a sturdy and reliable manner.

Further objects are to provide a circuit interrupter of the reclosing type which is so made that it may be readily converted from a lock-in circuit interrupter to a lock-out circuit interrupter or vice versa with a minimum of alterations and in a very simple and easy manner.

An embodiment of the invention is shown in the accompanying drawings, in which:

Figure 1 is a vertical sectional view through the circuit interrupter, such view showing the circuit interrupter in closed position.

Figure 2 is a sectional view on the line 22 ure 1.

Figure 3 is a sectional view on the line 33 of Figure 2.

Figure 4 is a sectional view on the line 4-4 of Figure 1.

Figure 5 is a view corresponding to Figure 1 of the upper portion of the circuit interrupter showing the position of the parts when the circuit interrupter is locked out.

Figure 6 is a fragmentary view partly broken away showin the lock-in mechanism.

Figure 7 is a view taken at right angles to Figure 6.

Figure 8 is a perspective fragmentary view partly broken away showing a part of the lock-in mechanism detached from the remainder of the apparatus.

Figures 9 and 10 are views showing respectively a lever and a plate which may replace the lever and plate of the circuit interrupter which is used when the circuit interrupter is converted into a lock-out circuit interrupter.

Figure 11 is a diagrammatic view showing the way in which the circuit interrupter is connected in a distribution system.

The circuit interrupter is housed within a metal tank whose body portion is indicated by the reference character 1 and whose top or cover portion by the reference character 2. The circuit interrupter may be supported from a pole or other suitable support by means of a bracket 3 carried by the body portion 1. The body portion 1 is filled with oil up to the oil level indicated in Figure 1.

The circuit interrupter comprises a body portion of magnetic material consisting of an upper magnetic memher 4 and a lower magnetic member 5 spaced apart by magnetic side members 6. A solenoid or magnet coil 7 is positioned between the upper and lower magnetic members. The lower magnetic member is provided with a magnetic plug 8 through which the non-magnetic extension 9 of the magnetic plunger 10 passes.

The switch mechanism of the circuit interrupter may be like that disclosed in the copending application in which I am the joint inventor with Carl Schindler, Serial No. 585,238, filed March 28, 1945, now Patent No. 2,560,831, July 17, 1951, for Circuit Interrupter, assigned to the same assignee as this application. Briefly, it may consist of a pair of stationary contacts 11 mounted on the outer side of a pair of spaced insulating plates 12 and connected in series with the coil 7 between the terminals of the circuit interrupter. The stationary contacts 11 are adapted to be electrically connected together, when the circuit interrupter is closed, by means of a pair of movable contacts 13 carried by insulating levers 14 and electrically connected by the transversely extending metallic bar or rod 15.

The switch levers or arms 14 are pivoted as indicated at 15' and are rocked back and forth as the tension spring 16 is moved from one side to the other across the pivot point 15'. The spring 16 has one end supported from the rod 15 by means of insulating sleeves 17 and has its other end secured to the pin 18 carried by the guide lever 19. The guide lever 19 is rocked about its pivot 20 by means of a lever 21 which is connected to the lever 19 by means of a link 22. The levers 19 and 21 may be formed of a pair of identical members and such levers and the link 22 are formed of insulating material.

The lever 21 carries a roller 23 at its free end which is engaged by the extension 9 of the operating magnetic plunger 10.

The spring 16 never crosses the pivot 20 of the guiding lever 19 and consequently it always causes an upward force to be exerted by the roller 23 against the lower face of Fig- 3 of the extension 9 of the plunger 10, thus biasing the plunger upwardly towards its initial position.

All parts of the circuit interrupter are supported from the cover 2. The cover 2 also carries a rock shaft 24 provided with an externally located handle 25 normally housed within a casing 2.6 and adapted to be manually operated to trip the circuit interrupter or to reset it. The handle 25 is preferably formed as an eyeletso as to .receive a switch stick. The rock shaft 24 rigidly carries a small lever 27, see Figures 1 and 4.

A bell crank lever 28, 29 is loosely mounted upon the shaft 24 and its arm 28is connected by means of an insulating link 30 with the operating plunger it) as shown in Figure l. A second' lever 31 is also loosely mountedon the shaft 24 and is pivoted as indicated at 32 to a channelshaped link 34 which, together with the link 35, constitutes a toggle link mechanism. The link 35 is pivoted to the link 34 as indicated at 35 and has its inner end pivoted as indicated at 37 to a fixed point in the cover 2. It will be seen that the link 35 extends into the channel of the link 34- and thus constitutes a stop to limit the downward motion of the toggle link mechanism. The construction is such that when the parts are in the position shown in Figure l, the toggle link mechanism is just past dead center and, therefore, locked against collapsing. The link 35 is urged downwardly by means of the light spring 38.

The lever 31 is provided with an extension 39 and a spring 49 is interposed between the lever 27 and the extension 39 of the lever 31. The spring 40 normally holds the small lever 27 in contact with the stop 41 formed on the extension 39 of the lever 31. It, however, allows the small lever 27 to be rocked upwardly when the operator pulls downwardly on the handle 25. When the lever 27 rocks upwardly, it strikes the under side of the link 34 of the toggle link mechanism and thus breaks the toggle link mechanism causing the parts to move to the position shown in Figure 5 under the influence of the spring 42, see Figures 4 and 5. It is to be noted that the pivot or pin 32 carried by the lever 31 strikes the arm 29 and rocks the arm 28 downwardly, thus depressing the plunger 10 and opening the switch with a quick motion.

Resetting is accomplished by rocking the handle 25, see Figure 4, upwardly. This rocks the lever 27 which engages the stop 41 on the lever 31 and rocks the lever 31 to the position shown in Figure 1', thus straightening out the toggle, the light spring 35, see Figure 1, moving the toggle slightly past dead center. it is to be noted that the circuit interrupter can now close. Also it is apparent that if an overload should occur, even while manual resetting is taking place, that no blow is transmitted to the manually operable lever 25.

A pump indicated generally by the reference character 4-3, see Figure l, is provided and consists of a cylinder 44 and a piston 45 provided with a check valve 46. The piston 45 is connected to the bell crank lever 28, 25, by means of an insulating link 47 so that the pump is operated each time the plunger it executes a down stroke.

The pump pumps oil into the counting cylinder 48 of counting means indicated generally by the reference character 4-9 and raises the counting or cumulative piston 56 a certain predetermined distance for each stroke of the plunger. A check valve 51 is positioned between the pump and the cumulative means 49. A weighted valve 52 is carried by the piston 59 and allows slow settling of the piston by means of the leaking of the oil around the weighted valve 52.

The counting or cumulative means indicated generally by the reference character 49 performs two functions, One of the functions is to enact with the other portions of the circuit interrupter to provide a two-time current characteristic for the circuit interrupter. In other words, the circuit interrupter is so designed that it has one or more quick opening operations followed by one or more delayed circuit opening operations. The other function which is performed by the cumulative means indicated generally at 49 is to lock in the circuit interrupter after a predetermined number of circuit interrupting operations occurring in rapid succession.

The purpose of this construction is to provide a circuit interrupter that has the characteristic of first clearing the circuit by a quick opening operation and thereafter closing the circuit and repeating this performance one or more times, as stated, so that if the fault is a temporary fault, no permanent interruption of the service occurs. However, if the fault is one which is a permanent fault, the circuit interrupter after executing one or more quick opening operations, thereafter executes one or more delayed operations. The purpose of this is to allow fuses coordinated with the circuit interrupter and following the circuit interrupter to blow and thus clear the defective branch line. If, on the other hand, the fuse should not be properly coordinated with the circuit interrupter, the circuit interrupter will lock closed, thus causing the fuse to blow. On the other hand, if there was no fuse whatsoever in circuit through inadvertence the circuit interrupter forming the subject matter of this invention will lock closed and will cause the preceding repeating circuit interrupter to finally. lock open.

In order to provide the two-time current characteristics hereinabove discussed, the piston 5%: of the cumulative means is arranged to cover a port or opening 53 in the cylinder 4-3. This opening 53 communicates with a passage 54 which in turn communicates with the cylinder or the space 55 below the magnetic plunger 10. A very light slide valve 56 is arranged to slide in an enlarged portion 57 of the space 54 and normally rests upon a shouldered part 53 as shown in Figure 3. This slide valve moves upwardly quickly when the plunger 10 descends and uncovers the port 53 and allows the free dis charge of oil from beneath the magnetic plunger iii. The slide valve is provided with a small opening 59 which is closed by the top plate 61 when the slide valve has moved upwardly to the upper limit of its stroke. The oil below the plunger 10 can discharge through the port 53.

The circuit interrupter is delayed in its closing stroke as the plunger 10 has to draw oil into the space 55 as the plunger 10 rises. This draws the slide valve 56 downwardly and the oil has to flow through the aperture 59 of the slide valve into the space 55 below the plunger 10, thus providing a delayed upward stroke for the plunger. The switch mechanism as previously described, however, executes a final quick closing stroke.

The plate 60 is provided with a plurality of holes 61 for the escape of oil from above the slide valve 56.

It is apparent that as the piston 5t) rises, that after a predetermined distance, it will close the port 53 and consequently the downward stroke of the plunger lt will be delayed as the oil trapped below the plunger it) has to escape around the plunger through the slight clearance between the plunger 10 and the main body portion or upper magnetic portion 4 of the structure.

The cumulative or counting means 49 is so constructed that it will reset itself after an interval of time as the piston 5% will settle downwardly due to the slow leak of oil around the valve 52 and will thus be in position for another series of operations. All of the above features have been described in detail in the copending application Se rial No. 585,238, now Patent No. 2,560,831 supra, hereinabove identified.

The second function accomplished by the cumulative means 49 is the locking of the circuit interrupter in closed position. for a predetermined length of time after a predetermined number of operations. This is accomplished by providing a lever 66 which is pivoted on a pivot pin 63 carried by upstanding ears ti t and '55, see Figure 8, formed on the plate 60. The lever 66 is spring urged downwardly by means of the spring 62., see Figure 2. It is to be noted that the lever 66 is provided with an out- '5 wardly projecting portion 67 which carries a leaf spring 68, see Figure 6. This leaf spring 68 fits within a notch 69 formed in the upper end of a bell crank lever 70. The bell crank lever is provided with a lower projecting arm 71 adapted to cooperate with an overhanging portion 72 of the bracket 73 which pivotally supports such lever and thereby limits the inward rocking motion of the upwardly extending arm 70 of such bell crank lever. The upwardly extending arm 70 of the lever is provided with a lip 74 which constitutes a latch adapted to fit within a notched portion 75 on the magnetic plunger as shown in Figure 6, under conditions hereinafter to appear and to thus lock the plunger 10 in its uppermost position. Normally, however, the lever 70 is held in its retracted position as shown in imaginary lines in Figure 6 so that the locking lip 74' is clear of the plunger 10 and does not engage the shouldered portion 76 thereof. The plunger, therefore, is normally free to be drawn downwardly on overload. However, when the latch lever 70 or upwardly projecting lever is rocked to the full line position shown in Figure 6 it is apparent that it will lock the plunger 10 in its uppermost position. The bottom part of the latching lever 74 is beveled so that the plunger can ride upwardly past such beveled portion on its last upward stroke prior to being locked closed.

The operation of locking the circuit interrupter closed occurs after the circuit interrupter has executed a predetermined number of opening operations occurring in rapid sequence. it is apparent that after a predetermined number of operations, the piston 50 of the counting means or cumulative means 49 will rise to a point where the valve portion 52 of such piston strikes the under side of the lever 66, see Figure 6, and thus raises the lever and rocks the latch lever 70 inwardly by means of the leaf spring 68. Under these conditions, as soon as the plunger 10 rises to its upper position, the latch lever 70 will snap into locking position as shown in Figure 6, the leaf spring 68 yielding and allowing the latch to move outwardly when the upper portion of the plunger rides below the main part of the latching tongue or finger 74 of the latch lever 70. Thus the circuit interrupter will be locked closed.

If it is desired, all of the operations of the circuit interrupter may be rapid. This is accomplished by removing the plug 79, see Figure 2. Obviously the length of the piston 50 will determine the number of fast operations before the port 53 is closed. Further, all of the operations may be delayed as a spacer may be placed below the piston 50 so that it keeps the port 53 closed at all times.

The wiring diagram is shown in Figure 11. In this diagram, a portion of the distribution system is shown. The reference characters A indicate repeating lock-in circuit interrupters forming the subject matter of this invention and the reference character B indicates a repeating lock-out circuit interrupter such as shown in the above noted copending application Serial No. 585,238, new Patent No. 2,560,831, supra. The circuit interrupters A are followed by branch lines C, each of which is provided with a fuse D. It is obvious that if an overload occurs on one of the branch lines, that the circuit interrupter A will operate to open the circuit. If a fault is temporary, nothing further happens. However, if the fault persists, the circuit interrupter A will execute one or more quick opening operations followed by one or more delayed opening operations. During the delayed opening, it is apparent that normally the fuse D of the overloaded branch line will blow. If the fuse D is not properly coordinated with the circuit interrupter and is too large, the circuit interrupter A will lock closed and cause the fuse to blow. Further than this, if the fuse D is properly coordinated with the circuit interrupter A, it is apparent that the circuit interrupter A does not have to lock closed as the fuse D will blow on the delayed opening period of the circuit interrupter A. Thus, it is apparent that a double protection is afforded by the circuit interrupter A so that on normal operation the fuse D on delayed opening of the circuit interrupter A will blow, but which if the fuse is too large, nevertheless is so constructed that it will ultimately lock closed so as to force the fuse D to blow.

The circuit interrupter forming the subject matter of this invention is a lock-in circuit interrupter. However, it can be changed to a lock-out circuit interrupter if so desired. All that is necessary is to remove the plate 60, see Figure 2, the bracket 73 and the associated parts and replace the plate 60 with the plate 77, see Figure 10, and also to replace the lever 35 of the toggle link mechanism, see Figure 1, with the insulating lever 78, see Figure 9. Under these conditions, the circuit interrupter will be of the same general type as that shown in the above noted copending application Serial No. 585,238 new Patent No. 2,560,831 of July 17, 1951, issued to Anthony Van Ryan and Carl Schindler. Obviously, it is a simple matter to change a circuit interrupter of the look-out type such as shown in the copending application into a lock-in circuit interrupter as disclosed hereinabove or vice versa.

It will be seen that a circuit interrupter has been provided which has a dual time current characteristic and which has a final lock-in. It will also be seen that the circuit interrupter is easy to change over from a lock-in to a lock-out circuit interrupter or vice versa.

Although this invention has been described in considerable detail, it is to be understood that such description is intended as illustrative rather than limiting as the invention may be variously embodied and is to be interpreted as claimed.

I claim:

1. A circuit interrupter having two time current char-- acteristics comprising electro-magnetic means including an energizing coil and an armature, switch means operated from said armature and arranged to open on overload, cumulative means adapted to be advanced in a stepby-Step manner upon successive operations of said circuit interrupter, normally ineffective time delay means for delaying the opening of said circuit interrupter, said time delay means being controlled by said cumulative means and becoming effective when said cumulative means has been advanced to a predetermined intermediate position, and normally ineffective lock-in means controlled by said cumulative means and rendered effective by said cumulative means when said cumulative means has been advanced to a position beyond said intermediate position.

2. A circuit interrupter having two time current characteristics comprising electro-magnetic means including an energizing coil and an armature, normally closed switch means operated from said armature and arranged to open on overload, hydraulic time delay means for delaying the opening of said circuit interrupter, said time delay means being normally ineffective and including a discharge opening, hydraulic cumulative means adapted to be advanced upon each operation of said circuit interrupter and positioned to constrict said discharge opening when advanced to an intermediate position, and normally ineffective lock-in means for locking said circuit interrupter in closed position, said lock-in means being controlled by said cumulative means and being rendered eflective by said cumulative means when said cumulative means is advanced to a position beyond said intermediate position.

3. A circuit interrupter comprising a magnetic plunger arranged to occupy a first and a second position, a solenoid for moving said plunger in one direction from said first position to said second position upon the occurrence of an overload, switch means actuated from said plunger and opened when said plunger is moved in said one direction to said second position, said plunger being biased towards said one position and having a shoulder formed thereon, a latch adapted to be moved into the path of movement of said shoulder to lock said switch means closed, and cumulative hydraulic means operated by said plunger in a step-by-step manner to an ultimate position in response to successive movements of said plunger from said first position to said second position within predetermined time intervals, said ultimate position of said cumulative means moving said latch to a latching position. 7

4. A circuit interrupter comprising armagnetic plunger arranged to occupy a first and a second position, a solenoid for moving said plunger in one direction from said first position to said second position upon the occurrence of an overload, switch means actuated from said plunger and opened when said plunger is moved in said one direction to said second position, said plunger being biased towards said one position and having a shoulder formed thereon, a latch adapted to be moved into the path of movement of said shoulder to lock said switch means closed, cumulative hydraulic means operated by said plunger in a step-by-step manner and having a gradual advance due to its cumulative action and actuating said latch towards latching position in the final position of said cumulative means, and a spring interposed between said cumulative hydraulic means and said latch, said latch having a tapered face to allow said plunger to move from said second position back to said first position whereby said latch engages said shoulder to latch said plunger in said first position.

References Cited in the file of this patent UNITED STATES PATENTS 2,506,744 Schindler et a1 May 9, 1950 2,530,298 Harper Nov. 14, 1950 2,560,831 Van Ryan et al July 17, 1951 2,568,155 Hubbard Sept. 18, 1951 2,573,234 Wallace et al Oct. 30, 1951 2,626,329 Wallace et al Jan. 20, 1953 

